1. Field of the Invention
The present invention relates generally to ignition devices for rocket motors and more particularly to such ignition devices for the rocket motor of a missile.
2. Description of the Prior Art
As is generally well known in the art, missiles of the type designed for launching from aircraft are generally mechanically detached from the aircraft whereupon the rocket motor within the missile is then ignited such that the missile is then capable of flight under its own power. The rocket motor of the missile must be ignited by a device and it is to this ignition device that the present invention addresses itself.
It has been proposed that the ignition device be initiated electrically. Initiation is either instantaneous with or delayed until after mechanical detachment of the missile from the aircraft. This proposal can be unsatisfactory in that electrical initiation is susceptible to interference by radar systems leading to the possibility of preignition occurring either accidentally or deliberately by an enemy agency. In addition, the use of delayed electrical initiation necessitates the provision of an electrical supply within the missile, thereby producing additional weight and space problems.
It has also been proposed that the ignition device be initiated by a mechanical system, for example, by a clock-work device or the triggering of a spring-loaded plunger. Such mechanical systems, however, rely upon energy stored mechanically within the missile, for example, in the springs of the clock-work device or the spring of the spring-loaded plunger. Thus, these mechanical systems tend to be bulky and involve weight problems, and the inherent moving parts can stick or jam with only limited stored energy available to cause them to function. Thus, as well as creating weight and space problems, reliability is questionable.
The present invention, by using a pneumatic fluid to drive a striker to impact a percussion-operated priming device, provides an ignition device which overcomes the problems and disadvantages of the prior art devices discussed supra.